Color television recording and reproducing system



June 7, 1966 NoBurosHl KxHARA 3,255,303

COLOR TELEVISION RECORDING AND REPRODUGING SYSTEM Original Filed March2.

2 Sheets-Sheet 1 f/@MMM M4 W June 7, 1966 NoBUTosI-n KIHARA 3,255,303

COLOR TELEVISION RECORDING AND REPRODUCING SYSTEM Original Filed March2. 1961 g Sheets-Sheet, 2

I I 40 3Q Y 4 1 1 1 f TRANSMISSION TR/IIIsM/ss/UN CHARACTER/STICCHARACTER/ST1@ FOR Y SIM/AL FOR compos/TE I IIIID Q SIG/VAL l 1 2 5 FREUENCY (Mc) 225 Q FREQUENLY (Mc) RECORDED- Y I Q Y I Q zo REPRODUCED JVIDEO SIe/IAL 22 22 l I Q) Y I Q Y DELAYED 25 VIDEO SIC-NAL OUTPUT @D YY Y y 2q OF SW/TFHINCT WWWWWWUI CIRCUIT OUTPUT I'+ Q I+ Q I'+Q I Q 30 0FSWITLHIII www CIRCUIT l'rLzsnTcIr' `reproducing a composite color signalof this type.

3,255 303 COLOR TELEVISIN RECORDNG AND REPRGDUCING SYSTEM NoliutoshiKx'hara, Tokyo, Japan, assignor to Sony Corporation, Tokyo, Japan, acorporation of Japan Continuation of application Ser. No. 2,359, Mar. 2,

1961. This application .inne 15, 1964, Ser. No. 375,159 Claims priority,application `Iapan, Mar. 7, 1960, 35/ 7,638 8 Claims. (Cl. 178-5.2)

This invention relates to a television signal transmission system andmore particularly to a system using magnetic tape recording andreproducing yapparatus for recording and reproducing color televisionsignals. The system of this invention has extremely low coloraberration, has minimum band width requirements in signal transmissionchannels thereof and yet is comparatively simple and very reliable inoperation.

This application is a continuation of a copending application, SerialNo. 92,859, led March 2, 1961, now abandoned. v

The invention was evolved with the general object of overcomingdiiculties which have been encountered in attempting to record andreproduce color television signals of the type approved by the NationalTelevision System Committee and the Federal Communications Commission.Such signals include a luminance signal, generallydesignated as la Ysignal, which may be used alone and directly in black and whitereproduction, and a phase-amplitude-modulated subcarrier chrominancesignal added -to the luminance signal. The carrierchrominance 'signalconsists of two component signals, usually designated as I and Osignals, which have a phase difference of 90 Vwith respect to eachother. To permit proper demodulation of the carrier-chrominance signals,a burst of a 3.58 mc. subcarrier signal is transmitted following eachhorizontal synchronizing pulse, on the back porch of the horizontalblanking pedestal. The burst is used-to synchronize an oscillator in thereceiver.

Various diticulties are encountered in recording and In particular, dueto unavoidable Variations in the speed of movement of the magnetic tape,the carrier-chrominance, luminance and synchronizing signals may bedelayed with respect to one another to produce a jitter etiect andsevere color aberration. In addition, `an extremely broad frequency bandwidth is required, producing additional troubles. Y

With the system of this invention, the jitter of the recording orreproducing head and recording medium does -not cause color aberrationand in addition, the required band width in the transmission channels isgreatly reduced. At the same time, however, the system is readily usablewith camera and reproducing systems designed for signals of the typeapproved by the National Television System Committee and the FederalCommunications Commission, and maintains the compatibilitycharacteristics of such systems. It is however noted that many featuresof the invention are not limited to use in conjunction with suchapproved signals, and many features are not limited to use inconjunction with a magnetic tape recording or reproducing system, andcan be used in conjunction with other types of signal transmissionmeans.

According to this invention, a single video signal is transmitted in theform of a set of component signals produced cyclically inline-sequential staggered relation at a submultiple of the line rate,and such component signals correspond to a set of component signalsgenerated 3 ,255,303 Patented June 7, 1966 ice simultaneously inaccordance with the scanning of an image `area. Such simultaneouslygenerated'component signals may preferably comprise a luminance or Ysignal and chrominance signals I and Q such as used in the approvedsystems discussed above. Such Y, I and Q signals maybe generated throughIa matrix circuit from color signals (red, green and blue) from a colorcamera, and they may be converted through a matrix circuit into similarcolor signals for reproduction.

According to an important feature of the invention, the transmittedvideo signal is in the form of a set of two component signals producedcyclically in line-sequential staggered .relation at one-half the linerate. One of such two component signals is divided in effect into lowerand upper frequency portions which respectively correspond to two ofthree simultaneously generated component signal-s, preferably the I andQ signals of an approved system. The other of the two line-sequentialsignals corresponds to the third simultaneously generated signal,preferably the luminance or Y signal of an approved system. Thisarrangement permits maximum use of the band'width of a signaltransmission channel, or conversely, permit-s high resolution withminimum band width requirements.

It is an important feature of the invention that the video signal can beproduced very simply and reliably through a switching circuitarrangementL and in the reproducing portion of the system, the videosignal can be readily converted into proper signals for reproduction,through a comparatively simple and very reliable delay and switchingsystem.

These and other objects, features and advantages of the invention willbecome more fully apparent from the following detailed description takenin conjunction with the accompanying drawings which illustrate apreferred embodiment and in which:

FIGURE 1 is a schematic diagram of a preferred form of signaltransmission system constructed according to the principles of thisinvention, wherein color television signals are converted to a signalwhich is recorded on a video tape recorder-reproducer, then subsequentlyreprolduced and converted to signals which are -applied to a picturetube or reproducer;

FIGURE 2 is a graph showing the transmission characteristics and bandwidth requirements for transmission of a Y signal;

FIGURE 3 is a graph similar to FIGURE 2 showing the 'transmissioncharacteristics for transmission of a composite I and Q signals; and

FIGURE 4 is a diagrammatic graphical illustration of the waveforms ofvideo signals produced at various points in the system.

In brief, the illustrated system comprises a conventional colortelevision camera 10 which produces red,

green and blue color signals on lines 11, 12 and 13.`

These signals are applied to a matrix circuit 14 which develops ablack-and-white or luminance signal Y on a line 15 and chrominancesignals Q and I on lines 16 and 17. The Y, Q and I signals are appliedthrough filter,

modulator and switching circuits to ultimately produce a composite videosignal on a line 18 which is applied to a video tape recorder-reproducer19. The video signal which is recorded may have a waveform ,such asdesignated by reference numeral 20 in FIGURE 4. As diagrammaticallyshown, horizontal synchronizing pulses 21 on blanking pedestals 22 aregenerated periodically at a line rate (15,750 per second) and the videosignal appears therebetween. The video signal` is of a linesequentialtype. During one line the luminance or Y signal is transmitted and thenduring the next line of the same field, a composite chrominance signalhaving I and Q components is transmitted, after which the Y signal istransmitted in the next line of the same field, etc.

The recorded video signal may then be reproduced and applied through aline 23 to the reproducing portion of the system. This signal is appliedto a delay circuit 24 arranged to produce a delay time exactly equal tothe duration of one line, for example 63.5 microseconds. The waveform ofthe delayed signal is indicated by reference numeral 25 in FIGURE 4. Thedelayed video signal, together with the undelayed signal are applied toa switching circuit 26 having A and B outputs at lines 27 and 28. Thiscircuit operates to apply to the A output on line 27 the Y signal duringone horizontal line and the delayed Y signal, designated by Y', duringthe next horizontal line of the same field, then the undelayed Y signalduring the next following horizontal line of the same eld, etc.Thisvoutput thus has a waveform as indicated by reference numeral 29 inFIGURE 4. Reference numeral 30 indicates the waveform produced at the Boutput line 28, which comprises a delayed chrominance signal, designatedby I' plus Q', developed during one horizontal line and an undel-ayedchrominance signal, I plus Q generated during the next horizontal lineof the same field.

The composite chrominance signal is then separated into its I and Qcomponents, the Q component is demodulated and the thus-generated Y, Qand I signals are applied to a matrix circuit 31 which develops red,green and blue color signals on lines 32, 33 and 34, such color signalslbeing applied to a reproducer 35.

Before entering into a more detailed description of the system, it isbelieved that it will be helpful to explain the system as approved bythe National Television System Committee and the Federal CommunicationsCommission. In the approved system, the luminance signal Y andchrominance signals I and Q are properly composed to become a colorsignal. Picture contents of two adjacent scanning lines of the samefield in a color picture as reproduced on a color picture tube arealmost the same, as if composed by the same color signal and even if thetwo scanning lines are modulated by the same color signal, anydifference cannot be recognized. This is especially true when the numberof the scanning lines is increased in one frame. Therefore, it will beapparent that if one scanning line is formed by signals including aluminance signal Y and the chrominance signals of one preceding scanningline of the same field (referred to as I' and Q) and the next scanningline is formed by signals including a luminance signal Y of onepreceding scanning line of the same field (referred to as Y) and thechrominance signal, so as to produce a sequence a faithful picture maybe reproduced.

In order to obtain such a signal sequence, it is necessary to pick upthe luminance signal Y and the chrominance signal (I-l-Q) alternated atevery other scanning line period, namely in the line sequence from theoriginal color signal and to delay the signals by one scanning lineperiod alternately in such a way that a luminance signal in which` the Ysignal and Y' signal are sequentially alternated at every other scanningline period and a chrominance signal in which the I+Q signal and I-{Q'signal are successively alternated at every other scanning line period.Since the Y and (I-i-Q) signals are made linesequential, there is noneed for any frequency interlock of the (I-f-Q) signal in the Y signalspectrum and there is no need for using the synchronizing burst signal.Accordingly, the frequency spectrum or band width is made so narrow thata vivid picture may be reproduced without color aberration.

It is generally considered suicient for the chrominance signals I and Qto have frequency band widths of 1.5 megacycles and 0.5 megacyclerespectively. According to an important feature of the invention, acarrier signal of 2.25 megacycles produced by an oscillator 36 ismodulated by the Q signal on line 16 by a modulator 37 to produce amodulated signal on a line 3S. The modulated signal produced online 38may have -a frequency spectrum as indicated diagrammatically byreference numeral 39 in FIGURE 3, to extend from approximately 1.5 to 3megacycles. The frequency spectrum of the I signal is indicateddiagrammatically by reference numeral 40! in FIGURE 3 and may be below1.5 megacycles as shown, so that both signals may be transmitted in acommon channel, without exceeding a total band width requirement of 3megacycles. The band width requirement for the luminance signal Y isgenerally considered to be 4 megacycles, but it can be reduced to about3 megacycles without appreciably affecting quality, and its spectrum mayhave a form as indicated by reference numeral 41. Accordingly, the bandwidth requirement for the luminance signal Y may correspond with theband width requirement for the composite chrominance I and Q signals.

The modulated Q signal on line 38 is applied to a switching circuit 42along with Y and I signals on lines 43 and 44. Lines 43 and 44 areconnected through circuits 45 and 46 to the matrix output lines 15 and17. Circuits 45 and 46 may provide delays to compensate or bal-ancedelays produced in the modulator 37 and may also include suitableband-pass filters.

The switching circuit 42 may take various forms but may preferablycom-prise three gate circuits 47, 48 and 49 connected between the inputlines 43, 38 and 44 respectively, and an adder circuit 50 having itsoutput connected to the line 18. They gate 47 is connected to one outputof a Hip-iop circuit 51 while the gates 48 and 49 are connected togetherand to the other output of the Hip-flop 51. The flip-Hop 51 is triggeredby horizontal synchronizing pulses from a synchronizing pulse generator52. In response to one horizontal synchronizing pulse, the fiip-op 51`may be triggered in one direction to open or enable the gate 47 whileclosing gates 48 and 49 to develop only the luminance signal Y at theoutput of adder 50. In response to the next horizontal synchronizingpulse, the flip-flop 51 is triggered in the opposite direction to enablethe gates 48 and 49 while closing gate 47 to thereby develop a compositeI and Q chrominance signal at the output of the `adder circuit 5t).

The synchronizing pulse generator applies horizontal and vertical driveand blanking pulses to the camera 10 through a line 53 and also appliesa composite synchronizing signal to the adder circuit 50 through a line54. This composite signal, may of course, include the horizontalsynchronizing pulses, vertical synchronizing pulses and equalizingpulses in conventional fashion.

It will thus be appreciated that the line-sequential signal having theform is produced at the output line 18, with a Waveform as indicateddiagrammatically by reference numeral 20 in FIG- URE 4, and is appliedto the video tape recorder-reproducer 19.

After the video signal is recorded, it is subsequently reproduced by therecorder-reproducer 19, or by a separate reproducer, and is appliedthrough the line 23 to the reproducing section shown in the lowerportion of FIGURE l. As above described, this section comprises thedelay circuit 24, which produces a time delay equal to the duration ofone scanning line, andthe switching circuit 26. Circuit 26 may takevarious forms but may preferably comprise a first pair of gate circuits55 and 56 and a second pair of gate circuits 57 and 58. Each set ofgates may be considered as forming the equivalent of a conventionalswitch having two contact points which may be selectively engaged by amovable contact point. Such switching devices are controlled by asynchronizing signal from a synchronizing signal separator 59 connectedto the line 23. In particular, a ip-flop 60 may be trig` gered byhorizontal synchronizing pulses from the separator 59 and may have one-output connected to gates 55 and 57 and a second output connected togates 56 and 58. When flip-op 60 is triggered by one horizontalsynchronizing pulse, gates 55 and 57 may be opened or enabled whilegates 56 and 58 are closed, to develop at the A output on line 27 theluminance signal Y while developing a delayed composite chrominancesignal l{-Q at output B on line 28. In response to the next horizontalsynchronizing pulse, the flip-flop 60 may be triggered in the oppositedirection to enable gates 56 and 58 While closing gates 55 and 57, tothereby develop a delayed signal Y' at the A output on line 27, whiledeveloping the undelayed'l-i-Q signal at the B output on line 28.

l Outputs are thus produced at the A and B outputs on lines 27 and 28,such as indicated diagrammatically by the waveforms 29 and 30 in FIGURE4.

The composite chrominance signal developed at out- Y put B on line 28 isapplied to a separator circuit 61 which may comprise, for example, afirst band-pass filter arranged to pass frequencies from 1.5 to 3megacycles land a second bandpass or low-pass lter arranged to transmitsignals from 0 to 1.5 megacycles. The modulated Q signal output of theseparator 61 is applied to a demodulator 62, the output thereof beingapplied to the matrix circuit through a line 63. The demodulator 62 maybe quite simple and may comprise, for example, a simple diode detectorcircuit.

The I signal output of the separator 61 is applied through a delaycircuit 64 to another input of the matrix circuit 31 and the A outputsignal developed at line 27 is applied through a delay circuit 65 tol-athird input to the matrix circuit 31. Delay circuits 64 and 65, providesuitable delays to compensate or balance for delays produced in thedemodulator and separator circuits.

As above indicated, the matrix circuit 31 may produce red, green andblue color signals which are applied through lines 32-34 to thereproducer 35. Horizontal and vertical synchronizing signals may also beapplied to the reproducer 35 from the synchronizing signal separator59.A

It will thus be appreciated that with this invention, there is notransmission of a complete col'or signal such as approved by theNational Television System Committee and the Federal CommunicationsCommission so that delays such as produced by jitter in the recordingand reproducing device do not affect the chrominance signal and there isno color aberration. At the same time, signals of the approved type canbe readily recorded and reproduced. l

Moreover, it is noted that a picture may be easily reproduced on a blackand white picture tube, by connecting the video input thereof to aterminal 66 connected through the delay circuit 65 to the line 27, ordirectly to the line 27 if desired. If the system is to be used solelyfor obtaining a black and White picture from a recorded color signal,the elements 56, 57, 61, 62, 64, etc. are not necessary.

The term chrominance signal is used in the claims as referring to anysignal relating to the chrominance value of `a light image. The term isthus used in a broader sense than the term carrier-chrominance signal asdefined at page l-40 of Fink, Television Engineering Handbook, l957, andis generic to the term chrominance component as defined at page l-42 ofFink.

The terminology continuous line-sequence signa Will be utilized in theclaims to refer to a signal wherein a succession of lines related to agiven image field are separated only by the usual horizontal retrace orblanking intervals, for example, Without any gap equal to the timeperiod of one scanning line. Of course as in the speciiic illustratedembodiment, each line of the continuous linesequence signal maycorrespond to a line of only one of the Y signal and the composite I andQ signal so that the term comprehends, for example, a periodicallyoccurring line sequence such as as shown in the rst part of FIGURE 4. y

It will be understood that modifications and variations may be effectedwithout departing from the spirit and scope of the novel concepts ofthis invention.

I claim as my invention:

1. A color signal recording and reproducing system comprising, in therecording system,

means for producing a plurality of color signals,

means comprising a matrix circuit for responding to said color signalsto produce a luminance signal and a chrominance signal,

means including switching means responding to the entire luminancesignal and the entire chrominance sign-al alternately in line-sequenceand providing only the entire luminance signal in one line interval bothof the latter signals comprising together a continuous line-sequencecolor signal, and only the chrominance signal in the next line interval,and

a magnetic recorder for recording said continuous linesequence colorsignal;

and in the reproducing system,

a magnetic reproducing device for reproducing said continuousline-sequence color signal recorded in said recording system,`

a delay circuit for delaying said continuous linesequence color signalby one scanning line period thereby obtaining a delayed continuousline-sequence signal including a delayed luminance signal and a 4delayedchrominance signal,

means including switching means for switching said continuousline-sequence color signal and said delayed continuous line-sequencesignal and for providing a line-sequence luminance signal consisting ofsaid luminance signal and said delayedfluminance signal alternating inline-sequence and a line-sequence chrominance signal consisting of saidchrominance signal and said delayed chrominance signal alternating inline-sequence,

means comprising a matrix circuit for obtaining a plurality of colorsignals from said line-sequence luminance and chrominance signals, and

means for reproducing a color picture from said color signals.

2. A color signal recording and reproducing system comprising, in therecording system,

means for producing red, green and blue color signals,

a matrix circuit for obtaining a luminance signal and two chrominancesignals from said color signals, a source of a carrier signal having afrequency outside the range of frequencies of one of said chrominancesignals,

means for modulating said carrier signal with the other of saidchrominance signals, thereby displacing t-he frequency band of saidother of said chrominance signals With respect to the signal frequencyband or said one of said chrominance signals in the frequency spectrum,

means for responding simultaneously to said one chrominance signal andthe modulated chrominance signal to form a composite chrominance signaland means for responding to'saidluminance signal and said compositechrominance signal alternately in line-sequence to provide a continuousline-sequence color signal, andb a magnetic recorder for recording saidcontinuous linesequence color signal;

and in the reproducing system,

a magnetic reproducing device for reproducing said continuousline-sequence color signal recorded in said recording system,

a delay circuit for delaying one part of said continuous line-sequencesignal by one scanning line period thereby obtaining a delayedcontinuous linesequence color signal consisting of delayed luminance anddelayed composite chrominance signals,

switching means consisting of two sections one of which is for switchingsaid continuous line-sequence color signal and the other of which is forswitching said delayed continuous line-sequence color signal,

said switching means having two output terminals at one of which acontinuous line-sequence luminance signal consisting of said luminancesignal and said delayed luminance signal alternating in line-sequence isobtained and at the other of which a continuous line-sequence cornpositechrominance signal consisting of said composite chrominance signal andsaid delayed composite chrominance signal alternating in linesequence isobtained,

a separator for separating said continuous line-sequence compositechrominance signal to obtain a rst chrominance signal and a secondmodulated chrominance signal which are substantially the same as thoseobtained in the recording system,

a demodulator for demodulating said second modulated chrominance signalto obtain a second demodulated continuous line-sequence chrominancesignal,

a matrix circuit for producing red, green and blue color signals fromsaid continuous line-sequence luminance signal and said first and secondchrominance signals, and

a color picture tube for producing a color picture from said red, greenand blue color signals.

3. A color signal recording system comprising means having a pluralityof color signal outputs,

means responsive to said color signal outputs for producing a luminancesignal corresponding to brightness of a scene and a chrominance signalcorresponding to the chromaticity of the image,

means for gating the entire luminance signal and the entire chrominancesignal alternately in continuous time sequence and providing only theentire luminace signal in one line interval and only the chrominancesignal in the next line interval, and

a magnetic recorder connected to said gating means.

4. A color signal reproducing system comprising a magnetic reproducerhaving only a luminance signal in one line interval and only achrominance signal in the next line interval,

a delay circuit connected to said magnetic reproducer output,

a iirst pair of gates connected to said magnetic reproducer output,

a second pair of gates connected directly to an output of said delaycircuit,

means for triggering one gate of each of said first and second pairs ofgates to producean output including the entire luminance signal in eachline interval and for triggering the other gate of each of said rst andsecond pairs of gates to produce an output including the entirechrominance signal in each line interval, and

means responsive to said luminance signal and said chrominance signalfor deriving a plurality of independent color signals.

5. A color signal recording and reproducing system comprising atelevision camera having a plurality of independent color signaloutputs,

means responsive to said color signal outputs for producing a luminancesignal and a chrominance signal,

means for gating the entire luminance signal and the entire chrominancesignal alternately in line-sequence and providing only the entireluminance signal in one line interval and only the chrominance signal inthe next line interval,

a magnetic recorder and reproducer connected to said gating means andhaving a continuous line-sequence color signal output,

a delay circuit connected to said continuous line-sequence color signaloutput,

means for gating said continuous line-sequence color signal output andan output of said delay circuit in continuous time sequence with respectto one another to provide a rst output including a luminance signal anda second output including a chrominance signal, and

means responsive to said luminance signal and said chrominance signalfor deriving a plurality of color signals each corresponding to arespective one of the plurality of independent color signal outputs.

6. An image signal recording system comprising means for providing afirst signal component generated in accordance with the scanning of animage area and having a relatively wide frequency spectrum andcomprising a first series of periodically occurring signals each havinga time period which is small in comparison with the time period forscanning of the image area and for providing second and third signalcomponents generated in accordance with the scanning of the image areaand having respective relatively narrower frequency spectrums whichoverlap each other and overlap the frequency spectrum of said rst signalcomponent and comprising second and third series of periodicallyoccurring signals each having the same time period as said first seriesof periodically occurring signals,

means for displacing the frequency spectrum of one only of said secondand third signal components to provide a displaced frequency spectrumlying immediately above the frequency spectrum of the other of saidfirst and second signal components,

means for combining at least every second one of the periodicallyoccurring signals of said one of said second and third signal componentswith respective periodically occurring signals of said other of saidsecond and third signal components to provide a composite signalcomponent comprising a series of composite signals having a frequencyspectrum substantially overlapping the frequency spectrum of the rstsignal component and for transmitting at least spaced composite signalsof the composite signal component which are separated by a one line timeperiod and for transmitting at least periodically occurring signals ofthe rst signal component which are separated by a one line time periodand which alternate in time with said spaced composite signal of thecomposite signal component.

7. A color signal recording system comprising a color television camerafor producing a plurality of color signals,

means for receiving said color signals and for producing a Y signalcomponent,

an l signal component and a Q signal component each comprising asuccession of periodically occurring signals containing information withrespect to the image viewed by said color television camera,

means for receiving said Y signal component,

said I signal component and said Q signal component from said receivingmeans and for modifying one of the I and Q signal components so as toenable the combining of corresponding periodically occurring signals ofthe one of said I and Q signal components and the other of said I and Qsignal components,

and including switching means for transmitting alternately aperiodically occurring signal of the entire Y signal component and thena periodically occurring signal of the entire I and Q signal componentsto provide an output signal comprising a succession `8. A color signalreproducing system comprising a magnetic recording device for'reproducing a color signal consisting of a succession of compositesignals which alternately contain only the Y signal information in oneline interval and only the combined I and Q signal information in thenext line interval ponent in one line interval and then a signal of thedelayed entire Y signal component in the next line interval and forproviding a second output signal consisting of a signal of the delayedentire I and Q signal component in the one line interval and then asignal of the entire I and Q signal component in the next line interval,and means comprising a matrix circuit -for receiving said rst and secondoutput signals and for providing a plurality of color signals therefrom.

References Cited by the Examiner UNITED STATES PATENTS with respect to acolor image,

a delay circuit for delaying said color signal by one 15 Ielh HE7-8 5scanning line period thereby obtaining a delayed r am 2,960,563 11/1960Anderson 178-5.4 color signal mcludlng delayed entire Y slgnal componentand a delayed entire I and Q signal com- 2993086 7/1961 De 'France17g-52 3,048,652 8/1962 Newell 1785.2

ponent, means including switching means for switching said color signaland said delayed color signal 20 and for providing a rst output signalconsisting al- DAVID G' REDINBAUGH Primary Examiner' ternately of asignal of the entire Y signal com- J. A. OB-RIEN, Assistant Examiner.

1. A COLOR SIGNAL RECORDING AND REPRODUCING SYSTEM COMPRISING, IN THERECORDING SYSTEM, MEANS FOR PRODUCING A PLURALITY OF COLOR SIGNALS,MEANS COMPRISING A MATRIX CIRCUIT FOR RESPONDING TO SAID COLOR SIGNALSTO PRODUCE A LUMINANCE SIGNAL AND A CHROMINANCE SIGNAL, MEANS INCLUDINGSWITCHING MEANS RESPONDING TO THE ENTIRE LUMINANCE SIGNAL AND THE ENTIRECHROMINANCE SIGNAL ALTERNATELY IN LINE-SEQUENCE AND PROVIDING ONLY THEENTIRE LUMINANCE SIGNAL IN ONE LINE INTERVAL BOTH OF THE LATTER SIGNALSCOMPRISING TOGETHER A CONTINUOUS LINE-SEQUENCE COLOR SIGNAL, AND ONLYTHE CHROMINANCE SIGNAL IN THE NEXT LINE INTERVAL, AND A MAGNETICRECORDER FOR RECORDING SAID CONTINUOUS LINESEQUENCE COLOR SIGNAL; AND INTHE REPRODUCING SYSTEM, A MAGNETIC REPRODUCING DEVICE FOR REPRODUCINGSAID CONTINUOUS LINE-SEQUENCE COLOR SIGNAL RECORDED IN SAID RECORDINGSYSTEM, A DELAY CIRCUIT FOR DELAYING SAID CONTINUOUS LINESEQUENCE COLORSIGNAL BY ONE SCANNING LINE PERIOD THEREBY OBTAINING A DELAYEDCONTINUOUS LINE-SEQUENCE SIGNAL INCLUDING A DELAYED LUMINANCE SIGNAL ANDA DELAYED CHROMINANCE SIGNAL, MEANS INCLUDING SWITCHING MEANS FORSWITCHING SAID CONTINUOUS LINE-SEQUENCE COLOR SIGNAL AND SAID DELAYEDCONTINUOUS LINE-SEQUENCE SIGNAL AND FOR PROVIDING A LINE-SEQUENCELUMINANCE SIGNAL CONSISTING OF SAID LUMINANCE SIGNAL AND SAID DELAYEDLUMINANCE SIGNAL ALTERNATING IN LINE-SEQUENCE AND A LINE-SEQUENCECHROMINANCE SIGNAL CONSISTING OF SAID CHROMINANCE SIGNAL AND SAIDDELAYED CHROMINANCE SIGNAL ALTERNATING IN LINE-SEQUENCE, MEANSCOMPRISING A MATRIX CIRCUIT FOR OBTAINING A PLURALITY OF COLOR SIGNALSFROM SAID LINE-SEQUENCE LUMINANCE AND CHROMINANCE SIGNALS, AND MEANS FORREPRODUCING A COLOR PICTURE FROM SAID COLOR SIGNALS.